Inserts offer a new angle on pediatric flat foot treatment

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BioMechanics January 2006

Inserts offer a new angle on pediatric flat foot treatment

By: J. Pettengill, DPM, and M. Jay, DPM

Many people have flat feet and the condition is widely recognized as

a cause of generalized foot pain and fatigue. People the world over

will purchase a seemingly infinite number of products to alleviate

their aches and pains. These encompass remedies ranging from powders

and pain medications to pads and pumice stones, expensive custom-

molded orthoses to invasive surgery. Most of these people are adults

trying to palliate what they believe to be the effects of normal wear

and tear on their feet. The truth is that some of these pains could

have been prevented had more attention been paid to their foot health

at an earlier age.

Children with flat feet often grow into adults with flatter feet.1,2

D'Amico has remarked that " developmental flatfoot is the most common

condition affecting the musculoskeletal system of children under six

years of age. " 2 Though children with flat feet may not have the same

complaints or symptoms as their adult counterparts, this does not

mean that their condition should go undiagnosed or untreated.

Children may not present with a chief complaint of arch pain or heel

cord tightness. Their symptoms may be disguised as tired or achy feet

or complaints that they can't run as fast as the other kids.

Pediatric flat foot

Development of the normal pedal arch is a topic of some debate. Some

authors contend that the arch is present at birth3 and that it is

obscured by a fat pad, which later disappears to reveal the skeletal

arch.4 Others write that the arch is absent at birth and slowly

develops over the first five years of a child's life.5,6

The clinical absence or collapse of this medial longitudinal arch is

commonly referred to as flat foot.1 This collapse is further defined

by Root, Orien, and Weed as the " abnormal pronation of the entire

foot which occurs at the subtalar joint. " 7 They explain that abnormal

pronation may be caused by compensation for structural abnormalities

of the foot or leg, response to forces that load the medial side of

the foot, or muscle imbalances caused by neuromuscular disease.7

While there are many classifications for flat foot, including

pathological versus physiological,8 congenital versus acquired,1 and

rigid versus flexible,9 only the flexible flat foot will be discussed

here. Flexible flat foot describes a foot with a normal arch on

nonweight-bearing that collapses during stance.10 Furthermore, it is

this foot type that an " overwhelming majority of beginning standers

and walkers " present with.3

Diagnosis

Diagnosis of a flexible flat foot in the pediatric patient must go

beyond clinical observation and visual inspection.11 A biomechanical

examination of the child, which includes measurements of the lower

extremities from hips to toes, is required. This examination should

include tests in both open and closed kinetic chain activities and an

analysis of the child's gait pattern.

Evaluation of the lower extremities begins at the hip. Infants are

born with 31 degrees to 38 degrees of femoral neck anteversion, which

presents clinically as internal rotation of the hips.4,12 Normal

ontogeny dictates that medial femoral torsion will reduce to 16

degrees to 21 degrees by adulthood.4 During the first year of

development the ratio of external to internal rotation of the femur

in the hip joint is 2:1.13 By the age of one this ratio becomes

closer to 1:1.12 These events culminate in symmetrical hip rotation

by about age six.13 At the same time, the distal one-third of the

tibia is undergoing external torsion starting at an axis of 0 degrees

to 10 degrees from the frontal plane and finishing at approximately

22 degrees .4 These developments work in conjunction to bring the

human foot plantargrade for ambulation. Root, Orien, and Weed have

outlined two of the causes of compensatory flexible flat foot as

being internal tibial and femoral torsion.7 It should also be noted

that increased medial load causing flexible flat foot has been

attributed to the converse: external tibial and femoral torsion.7

Measuring ankle dorsiflexion in the young child can diagnose primary

equinus as the cause of flexible flat foot, correction of which is

essential for normal foot function.9 and Todd report that less

than 20 degrees of ankle dorsiflexion from age zero to five may lead

to primary equinus later in life.9 Indeed, normal range of ankle

dorsiflexion at age three is 20 degrees to 25 degrees , which

diminishes to 10 degrees by age 15.13 Dorsiflexion at this joint

should be attempted with the knee both extended and flexed. Decreased

ankle dorsiflexion with both knee positions indicates a gastrocsoleal

equinus while limited dorsiflexion with knee extended only indicates

gastrocnemius equines.13 Limited ankle dorsiflexion can lead to

compensatory and abnormal subtalar joint pronation9 and, later,

flexible flat foot.

The forefoot-to-rearfoot relationship is extremely important when

evaluating the flexible flat foot. It is measured while the subtalar

joint is in neutral and the midtarsal joint is locked on the rearfoot

complex. In forefoot varus, the forefoot is inverted to the sagittal

bisection of the calcaneus; in forefoot valgus, it is everted. Both

are etiologies of flexible flat foot. Embryological development, as

put forward by Tax,3 determines that the foot is in an inverted

position in utero and begins to evert at the 16th week of pregnancy.

This eversion continues through the early childhood years, but

according to Tax, the forefoot may not become fully plantargrade in

time for ambulation.3 Compensation for the resulting forefoot varus

occurs through pronation at the subtalar joint and subsequent

eversion of the calcaneus.2,9 It has been estimated that a 4 degrees

forefoot varus will cause maximal pronation at the subtalar joint by

shifting the axis of body weight medially.9 For this reason D'Amico

has called forefoot varus the most destructive cause of flexible flat

foot.2

During ambulation or static stance, Root, Orien, and Weed explain

that " the abnormal pronatory motion or pronated position of the foot

is responsible for more chronic low-grade foot and postural

symptomatology than any other type of foot problem. " 7 As has been

mentioned, the etiology of the pronation is very important, and

furthermore, pronation that everts the calcaneus is considered more

pathological than that which allows the calcaneus to remain vertical

during weight-bearing.7

The angle of the posterior vertical axis of the calcaneus to the

supporting surface during stance is called the relaxed calcaneal

stance position. The RCSP is a measurement that indicates the

position of the calcaneus in the frontal plane after all compensatory

pronation has taken place at the subtalar joint.14 Its measurement is

a quick way to accurately determine the amount of pronation that is

present in a given foot. A bisection of the posterior surface of the

calcaneus of a normal foot, while relaxed in stance, should be

perpendicular to the supporting surface.14 If the calcaneus is

inverted to the transverse plane, then it is considered to be in

varus; if it is everted, then it is in valgus. One of the criteria

set forth for flat foot includes relaxed calcaneal valgus.1

Orthotic treatment

One recognized treatment for the flexible flat foot is a supportive

and functional foot orthosis.9 Orthotic therapy for the pediatric

flat foot is based on a simple premise. By maintaining the child's

foot in its proper biomechanical alignment during development, foot

function improves and deforming forces are limited.10,14 For this

reason it is essential that excessive pronation be neutralized as

soon as a child is old enough to stand.3 With proper alignment of the

foot during development, the goals are to improve the child's

function and to prevent future foot problems associated with flat

foot.10 Some of the problems associated with flat foot are painful

heel spurs, bunions, and hammertoes.15

Jay16 has outlined four criteria that a pediatric orthosis should

meet:

- accommodate structural deformity and protect the foot during

growth;

- offer enough rigidity for support but be flexible enough to allow

for normal foot motion;

- restore proper postural alignment of the foot; and

- be made of materials chosen to create a secure foot/orthosis

interface.

In addition, has put forth goals for the pediatric orthosis,

including reduction of discomfort, allowance for increased

participation in activity, reduction of normal shoe wear, and

reduction of abnormal pronation and calcaneal eversion at RCSP.10

Many practitioners base their use of pediatric orthoses on research

that indicates orthoses can limit pronation and correct RCSP16 and,

with time, improve the osseous relationships of the longitudinal

arch.4,17 Bleck credits this improvement to establishment of normal

equilibrium, allowing the ligaments in the arch to tighten.18 Some

authors argue that orthoses do not provide long-term cures for flat

feet, but these same authors often agree that shoe inserts may

provide relief of pediatric flat foot symptoms.5,6 In any case,

practitioners continue to value the orthosis as a viable option for

the treatment of pediatric flat foot.

The range of orthotic design is unlimited. The Whitman plate was a

steel device that made it uncomfortable to pronate.10 The Helfet heel

seat was made to reinforce the heel cup in the shoe and prevent

medial breakdown.10 The Schaffer design has a medial support but does

not provide control of calcaneal eversion.16 The UCBL (University of

California Biomechanics Laboratory) insert provides more control but

there are reports of sliding in the shoe and of the need for

modification, including a medial outrigger.10 The DSIS (Dynamic

Stabilizing Innersole System) offers better control of the rearfoot

and is a good option for the pediatric patient.19

Dynamic stabilizing innersole system

The DSIS, put forth by Jay and Schoenhaus in 1992, is an orthosis

that prevents hyperpronation of the foot by controlling all three

planes of motion at the subtalar and midtarsal joints.19 The device

is fitted with a deep heel cup that is offset with 5 degrees of varus

posting (Figure 1A), which works to limit calcaneal eversion in the

frontal plane and subsequent hyperpronation at the subtalar joint.19

The DSIS is also equipped with high medial and lateral flanges

(Figure 1B). These flanges prevent movement along the transverse

plane by preventing abduction of the forefoot at the midtarsal joint

and the spreading of the metatarsals, which both occur secondary to

pronation at the STJ.19 The medial flange provides support to the

medial arch of the foot and inhibits flattening in the sagittal

plane. Furthermore, the flanges have independent ranges of motion and

allow for plantar flexion of the first ray during propulsion, an

essential component to maintaining the medial longitudinal arch of

the foot and preventing first metatarsophalangeal arthritis or hallux

limitus.16,19

In 1995, Jay et al showed, in a study of 50 children with a mean age

of 5.5, that the DSIS was able to bring an average RCSP of

approximately 6 degrees of valgus to neutral.16 This orthosis is

beneficial to children ages two to 16 because as the foot is held in

alignment, the relationships of immature bones and joints are allowed

to develop optimally.14,19 In this manner the device not only serves

to limit pediatric flat foot symptoms but works to prevent painful

symptoms from occurring in adulthood.

Proposed treatment

Custom-molding orthoses for small children can become problematic

because their feet are constantly growing.3 This problem may be

approached by production of footwear that contain a built-in,

lightweight, molded insert that corresponds to the size of the shoe

and thus the foot.3 Tax states that " rubber orthotics or insoles of

similar materials that are firm enough to resist compression and

prevent abnormal arch depression while maintaining normal posting

values are excellent examples of suitable materials for children. " 3

The purpose of our project was to clinically evaluate the effects of

a new pair of shoes with functional inserts on a group of pediatric

subjects with normal and flat feet. A number of Buster Brown shoes

were manufactured for this study, each with a pair of built-in,

standardized, rubber pediatric DSIS. We hypothesized that these shoes

with inserts would be tolerated well by children with normal and

hyperpronated feet. Additionally, we hypothesized that those children

with symptomatic flat feet or those with " tired or aching feet " would

enjoy a reduction in symptoms over a three-month period. Significant

changes in biomechanical measurements were not expected during the

short duration of the pilot study. Thus, data collection was used to

enhance clinical impressions and conclusions.

Materials and methods

Twenty-six children between the ages of three and eight years

(average age four years) were evaluated with both a biomechanical

exam to establish foot type and a questionnaire to learn of any foot

fatigue symptoms that may or may not be due to flat feet. A total of

52 feet were evaluated in the study. The children were enrolled in

the study as volunteers through a local daycare without regard to

race, gender, or foot type. Symptomatic and asymptomatic children

were accepted. Exclusion criteria included a neuromuscular condition

(i.e., cerebral palsy) or any syndrome associated with joint laxity

(i.e., Ehlers-Danlos syndrome). Those children having rigid flat feet

due to such conditions as vertical talus or tarsal coalition were

also excluded. It should also be noted that proper Internal Review

Board approvals were obtained from the appropriate institutions.

Consent forms and questionnaires were sent home with all children who

volunteered for the study. The questionnaire was designed to be

answered by both the child and the parent and contained queries about

the exclusion criteria, family history, the activity of the child,

and how the child's feet felt during activity. In the parent's

section, for example, a question read, " Does your child complain of

foot fatigue after playing for a number of hours? If so, after how

many hours? " Foot fatigue was defined as a symptom and a subjective

finding. One example of a child's question would be: " How do your

feet feel after walking for a long time around the mall? The answers

to the questions in the child's section were in the form of a visual

analog scale using character faces: happy, indifferent, and sad

(Figure 2). Some questions pertaining to birth, family history, and

posture were included only for clinical correlation.

On the first visit to our office the children were given a

biomechanical exam and measured for shoe size. Each exam was

conducted by the same practitioner using the same equipment and

technique. The biomechanical exam included open and closed kinetic

chain measurements along with a gait analysis. The open kinetic chain

exam included measurements of hip rotation with respect to the

internal:external ratio, tibial torsion estimated by malleolar

position, ankle dorsiflexion with the knee extended and then flexed,

subtalar range of motion, and forefoot-to-rearfoot relationship. The

child was then asked to stand for examination of both the relaxed and

the neutral calcaneal stance positions (RCSP, NCSP, respectively)

while in the closed kinetic chain. Gait analysis followed and each

subject was evaluated for pronatory or supinatory motion in each of

the three periods of the gait cycle (contact, midstance, and

propulsive). Rigid flat foot was ruled out using Jack's test, or the

great toe extension test.14 The above biomechanical exams were

performed according to the methods outlined by Valmassy.13 A study by

Leung, et al was used to determine criteria for foot attitude during

the contact, midstance, and propulsive periods of gait.20

The shoes were ordered according to individual size and arrived

approximately three weeks later. The children and parents had a

choice between a buckle-type dress shoe for the girls and an oxford-

type hiker for the boys. A third alternative was a standard sneaker,

offered to both girls and boys. Each shoe had been fitted with a

standardized, rubber DSIS insert with a heel cup offset at 5 degrees

of varus and medial and lateral flanges as described earlier (Figures

3A and 3B). It is important to note that these inserts were not

custom made and were fitted to their corresponding shoe size at the

factory. The inserts were made of a rubber material firm enough to

resist excessive compression but flexible enough to allow normal

range of motion.

During the second visit, the shoes with inserts were distributed to

the children and each child was clinically evaluated for any symptoms

indicating improper shoe fit. If the shoes did not fit, they were

replaced with a pair that did fit from a stock of extra shoes. Also

at this time the parents were given a daily log to be filled out for

the next three months. This daily log contained three sections:

number of hours per day the shoes were worn, level of comfort of the

shoe with insert, and level of activity while wearing the shoe with

insert. Comfort level was measured simply as comfortable or

uncomfortable that day. Activity level was measured as low (equal to

one hour of playing outside and watching television the rest of the

time), medium (playing outside for four hours, for example), and high

(six or more hours of outside play time or playing in a competitive

sport). A section was also included for daily comments about the

shoes and inserts.

The third visit was a three-month follow-up. Each child was

clinically assessed for discomfort associated with the shoes and

inserts. Another biomechanical exam was performed at this time to

evaluate the children for changes that may have occurred with use of

the shoes with inserts. Each child and parent was given a follow-up

questionnaire in which they were asked the same questions as before

in order to determine the effect of the shoe with insert on foot

fatigue and how the child's foot " felt " during activity, etc. At this

time all daily logs were also collected and evaluated for the number

of hours per day the footwear was worn and for comfort and activity

level as outlined above. Parents unable to attend the third visit

were asked to submit their completed logs and questionnaires to the

daycare center or were interviewed via phone. Data significance was

tested by use of either the paired t-test or Fisher's exact test

where appropriate.

Results

The average age of the child in our study was 4 plus/minus 1.2 years

old with a median child's shoe size of 11 plus/minus 3. Fifty-four

percent of the subjects were boys. The open kinetic chain

biomechanical exam data for the first visit and the third, follow-up,

visit will be reviewed and compared. Examination of hip rotation

revealed the majority of the children (73%) had a 1:1

internal:external ratio of hip motion available when the knee was

flexed; 23% were internally rotated. One child, or 4%, had external

rotation at the hip. For the most part these values did not change

from visit one to visit three (except for an outlying value, visit

three, ID #20).

All of the children presented with external tibial torsion with an

average of 13.4 degrees plus/minus 4.2 degrees at the initial visit

and 14.2 degrees plus/minus 4.9 degrees at the third visit. The

difference between the values for the left ankle were not found to be

significant (P = 0.210) whereas, interestingly, the increase was

significant on the right (P = 0.036). All children were measured to

have ankle dorsiflexion within normal limits for their age range at

an average of 19 degrees plus/minus 6.1 degrees of dorsiflexion with

the knee extended and 28 degrees plus/minus 5.2 degrees with the knee

flexed. The values between visits one and three for ankle flexion

with the knee extended (right: P = 0.108, left: P = 0.448) and flexed

(right: P = 0.741, left: P = 0.307) were not found to be significant.

Subtalar joint range of motion was tested next and found to be well

within the normal limits at an average of 22 degrees plus/minus 5.7

degrees of available supination and an average of 12 degrees

plus/minus 4 degrees of pronation. The difference between visits one

and three was not significant (right: P = 0.254, left: P = 0.240 for

STJ inversion; right: P = 0.188, left: P = 0.726 for eversion). All

children measured had a vertical STJ neutral position. The forefoot-

to-rearfoot relationship was an average of 7 degrees plus/minus 4

degrees varus at visits one and three with no significant change

(right: P = 0.808, left: P = 0.808).

As for the closed kinetic chain biomechanical exam, the mean RCSP was

6 degrees plus/minus 3.8 degrees everted, which did not change

significantly from visit one to visit three (right: P = 0.425, left:

P = 0.086). Eighty-one percent of the children's heels were everted

in stance. Only four of the children were found to have heels that

were vertical in RCSP; all were found to have a vertical NCSP. Gait

analysis revealed that 81% of the study group pronated throughout the

gait cycle and only four children resupinated at the STJ during

midstance. These numbers correlate with the RCSP data. The children

who both had valgus RCSP and were pronated throughout the gait cycle

met the criteria for flat feet; 81% of the children exhibited

flexible flat feet.

According to the testimony of the parents, 27% (seven) of the

children experienced foot fatigue. Complaints varied from feeling

symptoms after only one hour of activity to after six to eight hours

of activity. After wearing the shoes with inserts for three months,

the number of children with complaints of foot fatigue dropped

significantly (P = 0.049) from 27% to 4% of the study population.

Additionally, the one child for whom symptoms continued enjoyed an

improvement in foot fatigue, complaining after eight to 10 hours of

activity instead of after only two hours. Put another way, it can be

reported that there was 100% improvement of symptoms with 88%

complete relief of symptoms. Interestingly, 15% of the children were

reported to have problems with tripping before the study began; after

they'd been wearing the shoes and inserts for three months, the

percentage of subjects with tripping problems was reduced to 4% (P =

0.349 [not significant]).

The questionnaire data provided by the children was also analyzed and

attention was again paid to before and after wearing of the shoes

with inserts (Figures 4 and 5). As evidenced by their answers to

queries, it was determined that an improvement of symptoms took place

in all categories. An improvement of symptoms after specific

activities was determined if a child circled a sad face on the first

questionnaire and an indifferent or happy face on the follow-up

questionnaire. A child going from indifferent to happy also counted

as an improvement.

Of course, a regression of symptoms would work in the reverse

fashion. According to answers given on the questionnaires, a

significant percentage of the children (38%, P = 0.001) experienced

an improvement in how their feet felt after running. Nineteen percent

(P = 0.029 [significant]) felt improvement in their legs, with only

4% regressing. Another 19% of the children

(P = 0.022 [significant]) had feelings of improvement in their hips.

In the questionnaires, 42% of the subjects (P = 0.006 [significant])

reported an improvement in how their feet felt after walking in the

mall, while only 8% experienced a regression of symptoms. Nineteen

percent of the children (P = 0.096 [not significant]) reported

feeling improvement while barefoot compared with only 4% regressing.

The data from the daily logs represented a three-month period with

varied shoe wear by the subjects. The children wore the shoes with

inserts for an average of 52 plus/minus 28 days, or approximately 58%

of the three-month study period. During these days, the shoes were

worn for an average of 7.6 plus/minus 2.7 hours. According to the

daily logs, the children considered the shoes comfortable 99.8% of

the time. On days the children were not comfortable, comments like

the child " felt sick today " or the child's " back had been aching, "

were reported. An estimated level of activity was determined by

assigning the numbers 1, 5, and 10 to the low, medium, and high

activity levels, respectively. Numerical assignment of the average

level of activity while wearing the shoes with inserts was 5

plus/minus 2.1, corresponding to a medium activity level.

Discussion

The values obtained from the initial biomechanical exam were not

statistically different from those taken three months later at the

end of the study (except for one data set involving external

malleolar torsion). This is not surprising; we never hypothesized

that any measurable biomechanical change would take place in a three-

month period. A longer term study would be needed to ascertain

whether any significant physical change would occur in the lower

extremities of those children wearing shoes with inserts. Taking into

consideration that children often require new shoes at least every

three months, tracking subjects in an extended study would present a

considerable challenge.

The majority of the children in the study presented with a 1:1

internal to external hip ratio, which coincided with normal ontogeny

after age six. The internally rotated hips of 23% of the children,

who ranged in age from three to five, may be explained by incomplete

reduction of femoral neck anteversion. This should correct itself

after they reach the age of six. One child presented with externally

rotated hips at the age of eight, which may represent a lack of

normal internal rotation of the hips. During the same growth period,

the tibia is undergoing external torsion. It was found that external

malleolar torsion on the right differed significantly from visit one

to visit three. This significance can be traced to a small number of

outliers who skewed the results of the t-test. It should also be

noted that an increase in malleolar torsion is acceptable, as this

change is consistent with normal ontogeny.

It was found that 24 of the 26 children presented with a forefoot

varus component (average 7 degrees varus). A 4 degrees forefoot varus

can shift body weight medially causing maximal pronation at the STJ.

Although the four children with supinated foot types and vertical

RCSP presented with forefoot varus, it was also noted that two of

these subjects possessed limited STJ eversion (#6, 16). This may

suggest that their ability to compensate for forefoot varus at the

STJ is limited.

The average RCSP for the group was 6 degrees of eversion with 81% of

subjects presenting with a flexible flat foot deformity. A number of

these flat feet may be secondary to a forefoot varus component. The

average RCSP of 6 degrees correlates with the average forefoot varus

of 7 degrees , as compensation at the STJ would occur in a 1:1 ratio.

Seven children (27%) presented with foot fatigue. That number dropped

significantly, to one child (4%), after three months of wearing the

shoes with inserts. Of the seven original children with foot fatigue,

six had flat feet and one had a rectus foot type (#19). Generalized

foot fatigue in those children with flat feet can be caused by

overuse of both the intrinsic and extrinsic foot musculature.

Improvement or relief of these symptoms can be attributed to the

ability of the shoes with inserts to maintain the child's foot in

proper alignment and allow for optimal foot function. Fatigue

associated with the rectus foot type may be attributed to factors

present in this child, such as internally rotated hips (2:1) or a

history of tripping recorded by his parents. It should be noted that

no in-toeing was present on exam. Although the hips did not

externally rotate by the third visit, foot fatigue and tripping had

ceased, as recorded by the parents. It is possible that the new shoes

fit the child better than former pairs or that the inserts offered

him more support. One child (#8) experienced an improvement in

fatigue but not a complete resolution, experiencing foot fatigue

eight to 10 hours after activity instead of after only two hours.

This child presented with flat feet and had recently been through a

growth spurt, which may have contributed to his foot fatigue.

A survey of the subjects using a system that could be understood by

children was a unique aspect of the study. In all of the categories,

including feet, legs, and hips after running and feet after walking

in the mall, there were significant improvements in how the child

felt between visits one and three. There were only small percentages

of regression in this area, which could be described as

insignificant. There was also an improvement in the way feet felt

after walking barefoot, but it was determined insignificant. Many of

these improvements in symptoms can be attributed to the construct of

the pediatric DSIS insert. The insert is made of a compressible

rubber amalgam that is soft enough to be comfortable but resilient

enough to offer support. Additionally, the individual medial and

lateral flanges allow for independent first- and fifth-ray range of

motion during early midstance, while ensuring stability in the arch

late in midstance.

Conclusion

This pilot study of the Buster Brown shoe with a pediatric DSIS

proved the hypothesis that the product would be well tolerated by

children with hyperpronated and normal feet. Furthermore, those

children with symptomatic flat feet and those with tired or aching

feet enjoyed a significant reduction in symptoms over a three-month

period. The children in the study were evaluated using a multitude of

methods including biomechanical examinations, daily logs, and

questionnaires aimed at both the children and their parents. Data

collection was used to enhance clinical impressions and conclusions.

The Buster Brown shoe with the pediatric DSIS proved to be an

important innovation in the treatment of children with flexible flat

foot and with generalized foot fatigue. This clinical trial showed

that the product is well tolerated by young children and, more

important, can improve symptoms 100% of the time. These data support

the product as an effective and less expensive short-term alternative

to costly custom-molded orthoses in the pediatric population. Further

research is warranted to determine long-term tolerance and/or

efficacy of this product.

J. Pettengill, DPM, is a second-year resident in the foot and

ankle surgical residency program at the Graduate Hospital in

Philadelphia. M. Jay, DPM, FACFAS, is residency director of

the program.

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